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Abstract:

The disclosure provides tissue webs, and products incorporating the same,
where the webs comprise macroalgae fibers. More specifically the
disclosure provides soft and durable tissue webs comprising at least
about 1 percent macroalgae fiber by weight of the web. In the tissue webs
of the present disclosure, macroalgae fibers may preferably replace high
average fiber length wood fibers, which increase the strength and
durability of the web without negatively affecting stiffness.

Claims:

1. A layered tissue web comprising a first air contacting layer and a
second fabric contacting layer, wherein the first air contacting layer
comprises from about 0.5 to about 5 weight percent macroalgae fibers by
weight of the web.

2. The layered tissue web of claim 1 having a Stiffness Index of less
than about 10.

3. The layered tissue web of claim 1 having an MD Durability Index of
greater than about 10.

4. The layered tissue web of claim 1 having a basis weight greater than
about 15 gsm, a geometric mean tensile index of at least about 30 and
geometric mean slope of less than about 10 kgf.

5. The layered tissue web of claim 1 having a geometric mean tensile from
about 700 to about 1000 g/3'' and a geometric mean slope from about 6.0
to about 9.0 kgf.

6. The layered tissue web of claim 1 having a basis weight from about 15
to about 45 gsm.

7. The layered tissue web of claim 1 wherein the second fabric contacting
layer is substantially free of macroalgae fibers.

8. The layered tissue web of claim 1 wherein the first air contacting
layer comprise from about 2 to about 4 weight percent macroalgae fibers
by weight of the web.

14. The layered tissue web of claim 10 having a basis weight greater than
about 15 gsm, a geometric mean tensile index of at least about 30 and a
geometric mean slope of less than about 10 kg.

15. The layered tissue web of claim 10 having a Stiffness Index of less
than about 10.

16. The layered tissue web of claim 10 having an MD Durability Index of
greater than about 10.

17. A method of forming a layered tissue web comprising the steps of: a.
dispersing a macroalgae dry lap pulp to form a first fiber slurry; b.
dispersing a conventional papermaking pulp to form a second fiber slurry;
c. depositing the first and second fiber slurries onto a forming fabric
such that the second fiber slurry contacts the forming fabric and the
first fiber slurry contacts the air to form a wet web; d. dewatering the
wet web to a consistency of from about 20 to about 30 percent; and e.
drying the wet web to a consistency of greater than about 90 percent
thereby forming a dried macroalgae tissue web.

18. The method of claim 17 wherein the macroalgae dry lap pulp has a
moisture content of less than about 10 percent and wherein the macroalgae
dry lap pulp comprises from about 1 to about 30 percent by weight of the
dry lap pulp macroalgae pulp fibers and from about 70 to about 99 percent
by weight of the dry lap pulp conventional papermaking fibers.

19. The method of claim 17 further comprising the steps of transferring
the dewatered web from the forming fabric to a transfer fabric traveling
at a speed from about 10 to about 40 percent slower than the forming
fabric; and transferring the web to a throughdrying fabric.

20. The method of claim 17 wherein the drying step comprises transferring
the dewatered web to the surface of a Yankee dryer and further comprising
the step of creping the dried macroalgae tissue web from the surface of
the Yankee dryer.

Description:

RELATED APPLICATIONS

[0001] The present application is a national-phase entry, under 35 U.S.C.
§371, of PCT Patent Application No. PCT/US2013/044891, filed on Jun.
10, 2013, which is incorporated herein by reference in a manner
consistent with the instant application.

BACKGROUND

[0002] Tissue products, such as facial tissues, paper towels, bath
tissues, napkins, and other similar products, are designed to include
several important properties. For example, the products should have good
bulk, a soft feel, and should have good strength and durability.
Unfortunately, however, when steps are taken to increase one property of
the product, other characteristics of the product are often adversely
affected.

[0003] To achieve the optimum product properties, tissue products are
typically formed, at least in part, from pulps containing wood fibers and
often a blend of hardwood and softwood fibers to achieve the desired
properties. Typically when attempting to optimize surface softness, as is
often the case with tissue products, the papermaker will select the fiber
furnish based in part on fiber length, aspect ratio and thickness of the
fiber cell wall. Unfortunately, the need for softness is balanced by the
need for durability. Durability in tissue products may be defined in
terms of tensile strength, burst strength and tear strength. Typically
tear strength and burst strength have a positive correlation with tensile
strength while tensile strength, and thus durability, and softness are
inversely related. Thus the paper maker is continuously challenged with
the need to balance the need for softness with a need for durability.
Unfortunately, tissue paper durability generally decreases as the average
fiber length is reduced. Therefore, simply reducing the pulp average
fiber length can result in an undesirable trade-off between product
softness and product durability.

[0004] Besides durability, long fibers also play an important role in
overall tissue product softness. While surface softness in tissue
products is an important attribute, a second element in the overall
softness of a tissue sheet is stiffness. Stiffness can be measured from
the tensile slope of stress--strain tensile curve. Generally, a decrease
in tensile slope results in lower stiffness, which typically provides
better overall softness. However, at a given tensile strength and slope
short fibers will display a greater stiffness than long fibers. While not
wishing to be bound by theory, it is believed that this behavior is due
to the higher number of hydrogen bonds required to produce a product of a
given tensile strength with short fibers than with long fibers. Thus,
easily collapsible, low coarseness long fibers, such as those provided by
Northern softwood kraft ("NSWK") fibers typically supply the best
combination of durability and softness in tissue products when those
fibers are used in combination with hardwood kraft fibers, such as
Eucalyptus hardwood kraft ("EHWK") fibers. While NSWK fibers have a
higher coarseness than EHWK fibers, their small cell wall thickness
relative to lumen diameter combined with their long length makes them the
ideal candidate for optimizing durability and softness in tissue.

[0005] Unfortunately, supply of NSWK is under significant pressure both
economically and environmentally. As such, prices of NSWK have escalated
significantly creating a need to find alternatives to optimize softness
and strength in tissue products. Another type of softwood fiber is
Southern softwood kraft ("SSWK"), which is widely used in fluff pulp
containing absorbent products such as diapers, feminine care absorbent
products and incontinence products. Unfortunately while not under the
same supply and environmental pressures as NSWK, SSWK fibers are
generally poorly suited for making soft tissue products. While having
long fiber length, the SSWK fibers have too wide a cell wall width and
too narrow a lumen diameter and thus create stiffer, harsher feeling
products than NSWK.

[0006] The tissue papermaker who is able to obtain pulps having a
desirable combination of fiber length and coarseness from fiber blends
generally regarded as inferior with respect to average fiber properties
may reap significant cost savings and/or product improvements. For
example, the papermaker may wish to make a tissue paper of superior
strength without incurring the usual degradation in softness which
accompanies higher strength. Alternatively, the papermaker may wish a
higher degree of paper surface bonding to reduce the release of free
fibers without suffering the usual decrease in softness which accompanies
greater bonding of surface fibers. As such, a need currently exists for a
tissue product formed from a fiber that will improve durability without
negatively affecting other important product properties, such as
softness.

[0007] Outside of softwood kraft pulp fibers very few options exist for
papermakers when seeking a satisfactory fiber to provide strength without
negatively impacting softness. Thus, there remains a need for alternative
papermaking fibers that may deliver softness while maintaining
satisfactory strength.

SUMMARY

[0008] It has now been discovered that macroalgae fibers, despite having a
relatively short average fiber length and high aspect ratios, may be
incorporated into a tissue web, and particularly the skin contacting
layer of a multi-layered web, also referred to herein as the air
contacting side or non-fabric contacting side, to yield webs having
improved strength without a significant increase in stiffness.
Surprisingly, these properties are particularly acute when macroalgae
fibers are substituted for wood fibers in relatively modest amounts, such
as less than about 5 percent, and more preferably less than about 3
percent, such as from about 0.5 to about 3 percent by weight of the web,
and when the fabric contacting layer of the web is substantially free
from macroalgae fibers.

[0010] In yet other embodiments the present disclosure provides a
multi-layered tissue web comprising a fabric contacting fibrous layer and
a non-fabric contacting fibrous layer, wherein the fabric contacting
fibrous layer is substantially free of macroalgae fibers and the
non-fabric contacting fibrous layer comprises from about 0.5 to about 5
percent by weight of the web macroalgae fibers, the tissue web having a
basis weight greater than about 35 gsm, a geometric mean tensile of at
least about 800 g/3'' and geometric mean slope of less than about 6 kg.

[0011] In still other embodiments the present disclosure provides a method
of forming a macroalgae tissue web comprising the steps of dispersing a
dry lap pulp comprising from about 1 to about 30 percent by weight
macroalgae to form a first fiber slurry, dispersing a conventional
papermaking pulp to form a second fiber slurry, depositing the second
fiber slurry onto a forming fabric, depositing the first fiber slurry
adjacent to the second fiber slurry to form a wet web, dewatering the wet
web to a consistency from about 20 to about 30 percent, and drying the
wet web to a consistency of greater than about 90 percent thereby forming
a macroalgae tissue web.

DEFINITIONS

[0012] As used herein the term "macroalgae fibers" refers to any
cellulosic fibrous material derived from red algae such as, for example,
Gelidium elegance, Gelidium corneum, Gelidium amansii, Gelidium robustum,
Gelidium chilense, Gracelaria verrucosa, Eucheuma Cottonii, Eucheuma
Spinosum, or Beludul, or brown algae such as, for example, Pterocladia
capillacea, Pterocladia lucia, Laminaria japonica, Lessonia nigrescens.
Macroalgae fibers generally have an aspect ratio (measured as the average
fiber length divided by the average fiber width) of at least about 80.

[0013] As used herein the term "red algae fiber" refers to any cellulosic
fibrous material derived from Rhodophyta. Particularly preferred red
algae fiber includes cellulosic fibrous material derived from Gelidium
amansii, Gelidium corneum, Gelidium asperum, Gelidium chilense and
Gelidium robustum. Red algae fibers generally have an aspect ratio
(measured as the average fiber length divided by the average fiber width)
of at least about 80.

[0014] As used herein the term "geometric mean tensile" (GMT) refers to
the square root of the product of the MD tensile strength and CD tensile
strength of the web, which are measured as described in the Test Methods
section.

[0015] As used herein, the term "slope" refers to slope of the line
resulting from plotting tensile versus stretch and is an output of the
MTS TestWorks® in the course of determining the tensile strength as
described in the Test Methods section. Slope is reported in the units of
grams (g) per unit of sample width (inches) and is measured as the
gradient of the least-squares line fitted to the load-corrected strain
points falling between a specimen-generated force of 70 to 157 grams
(0.687 to 1.540 N) divided by the specimen width. Slopes are generally
reported herein as having units of grams per 3 inch sample width or
g/3''.

[0016] As used herein, the term "geometric mean slope" (GM Slope)
generally refers to the square root of the product of machine direction
slope and cross-machine direction slope.

[0017] As used herein the term "Machine Direction Durability" generally
refers to the ability of the web to resist crack propagation initiated by
defects in the web and is calculated from MD Tensile Index (calculated by
dividing the MD Tensile Strength by the basis weight) and MD stretch
(output of the MTS TestWorks® in the course of determining the tensile
strength as described in the Test Methods section) according to the
formula:

Machine Direction Durability=0.6(MD Tensile Index0.74+MD
Stretch0.58)

[0018] As used herein, the term "Stiffness Index" refers to the quotient
of the geometric mean slope (having units of kgf) divided by the
geometric mean tensile strength (having units of g/3'') multiplied by
1,000.

[0019] As used herein the term "average fiber length" refers to the length
weighted average length of fibers determined utilizing a Kajaani fiber
analyzer model No. FS-100 available from Kajaani Oy Electronics, Kajaani,
Finland. According to the test procedure, a pulp sample is treated with a
macerating liquid to ensure that no fiber bundles or shives are present.
Each pulp sample is disintegrated into hot water and diluted to an
approximately 0.001 percent solution. Individual test samples are drawn
in approximately 50 to 100 ml portions from the dilute solution when
tested using the standard Kajaani fiber analysis test procedure. The
weighted average fiber length may be expressed by the following equation:

[0020] As used herein, the term "caliper" is the representative thickness
of a single sheet (caliper of tissue products comprising two or more
plies is the thickness of a single sheet of tissue product comprising all
plies) measured in accordance with TAPPI test method T402 using an EMVECO
200-A Microgage automated micrometer (EMVECO, Inc., Newberg, Oreg.). The
micrometer has an anvil diameter of 2.22 inches (56.4 mm) and an anvil
pressure of 132 grams per square inch (per 6.45 square centimeters) (2.0
kPa).

[0021] As used herein, the term "basis weight" generally refers to the
bone dry weight per unit area of a tissue and is generally expressed as
grams per square meter (gsm). Basis weight is measured using TAPPI test
method T-220.

[0022] As used herein, the term "sheet bulk" generally refers to the
quotient of the sheet caliper expressed in microns, divided by the dry
basis weight, expressed in grams per square meter. The resulting sheet
bulk is expressed in cubic centimeters per gram.

[0023] As used herein, the term "tissue product" generally refers to
various paper products, such as facial tissue, bath tissue, paper towels,
napkins, and the like. Normally, the basis weight of a tissue product of
the present invention is less than about 80 grams per square meter (gsm),
in some embodiments less than about 60 gsm, and in some embodiments,
between about 10 to about 60 gsm.

[0024] As used herein, the term "layer" refers to a plurality of strata of
fibers, chemical treatments, or the like, within a ply.

[0025] As used herein, the terms "layered tissue web," "multi-layered
tissue web," "multi-layered web," and "multi-layered paper sheet,"
generally refer to sheets of paper prepared from two or more layers of
aqueous papermaking furnish which are preferably comprised of different
fiber types. The layers are preferably formed from the deposition of
separate streams of dilute fiber slurries, upon one or more endless
foraminous screens. If the individual layers are initially formed on
separate foraminous screens, the layers are subsequently combined (while
wet) to form a layered composite web.

[0026] The term "ply" refers to a discrete product element. Individual
plies may be arranged in juxtaposition to each other. The term may refer
to a plurality of web-like components such as in a multi-ply facial
tissue, bath tissue, paper towel, wipe, or napkin.

DETAILED DESCRIPTION

[0027] In general, the present disclosure relates to tissue webs, and
products produced therefrom, comprising conventional papermaking fibers
and macroalgae fibers. It has been discovered that by replacing some of
the conventional papermaking fibers in the tissue web with macroalgae
fibers, and more specifically conventional fibers disposed in the
non-fabric contacting layer of a multi-layer tissue structure, that a
stronger and more durable web may be produced without sacrificing
softness.

[0028] The discovery that macroalgae fibers may be used to form soft,
strong tissue webs and more specifically that macroalgae fibers
displacing conventional fibers in the non-fabric contacting layer, is
particularly surprising provided the relative short length of macroalgae
fibers and their high aspect ratio. Table 1 compares the fiber properties
of three different fibers--hardwood, softwood and macroalgae.

For macroalgae pulp fibers, the ratio of length to width (commonly
referred to as the "aspect ratio") generally varies between about 120 and
about 250, although both length and width vary amongst species.
Generally, average fiber lengths for macroalgae fibers range from about
0.3 to about 1.0 mm, while fiber width varies from about 3 to about 7
μm. As shown in Table 1, macroalgae fibers are generally shorter than
both EHWK and NSWK fibers, but have significantly greater aspect ratios.

[0029] Despite the tendency of macroalgae fibers to have high aspect
ratios and short average fiber lengths it has now been surprisingly
discovered that they may be a satisfactory replacement for conventional
papermaking fibers in tissue webs. In particular, it has been
surprisingly discovered that selectively incorporating macroalgae fibers
into the non-fabric contacting layer of a multi-layered tissue structure
actually increases tensile strength without negatively effecting
stiffness. In fact, in certain instances, the increase in tensile may be
accompanied by only a slight increase in geometric mean modulus,
resulting in a web having a lower stiffness index. Previously, it was
believed that the greatest benefit was achieved when macroalgae fibers
were used to replace a portion of the long fiber fraction in the middle,
or non-skin contacting surface. However, it has now been discovered that
the beneficial effect on tensile and stiffness is particularly acute when
the macroalgae is substituted for convention papermaking fibers in the
non-fabric contacting layer of a multi-layered web as illustrated in the
tables below.

[0030] The macroalgae fibers are preferably derived from algae from the
Division Rhodophyta. More preferably the macroalgae fibers have been
subjected to processing to remove hydrocolloids, and more preferably
agar, from the cell wall. For example, macroalgae fibers may be processed
by extracting heteropolysaccharides as a cell wall component with hot
water, followed by freezing, melting and drying. More preferably the
macroalgae fibers are prepared using pulping methods known in the art
such as those disclosed in U.S. Pat. No. 7,622,019, the contents of which
are incorporated herein in a manner consistent with the present
disclosure. Regardless of the specific method of extraction, in certain
embodiments it may be desirable that the macroalgae fibers have been
processed such that the resulting fibers have an agar content of less
than about 5 percent by weight of the fibers, more preferably less than
about 3 percent by weight of the fibers and still more preferably less
than about 2 percent by weight of the fibers.

[0031] In certain embodiments the pulped macroalgae fibers may be
subjected to bleaching. For example, pulped macroalgae fibers may be
subjected to a two stage bleaching treatment using a chlorine dioxide in
the first stage and hydrogen peroxide in the second stage. In the first
stage 5 percent active chlorine dioxide by dry weight of the material may
be used to bleach the fiber at pH 3.5 and 80° C. for about 60
minutes. In the second stage, 5 percent active hydrogen peroxide by dry
weight of the material may be used to bleach the fiber at pH 12 and
80° C. for about 60 minutes.

[0032] The macroalgae fibers preferably have an average fiber length
greater than about 300 μm, such as from about 300 to about 1000 μm
and more preferably from about 300 to about 700 μm. The macroalgae
fibers preferably have a width greater than about 3 μm, such as from
about 3 to about 10 μm, and more preferably from about 5 to about 7
μm. Accordingly, it is preferred that the macroalgae fibers have an
aspect ratio greater than about 80, such as from about 100 to about 400
and more preferably from about 150 to about 350.

[0033] The macroalgae pulp fibers may be used as either dry or wet lap
pulps. In those embodiments where the macroalgae is used as a dry lap (a
pulp having a moisture content less than about 50 percent, more
preferably from about 1 to about 15 percent) it is preferred that it is
coprocessed with conventional papermaking fibers and more preferably that
the pulped macroalgae fibers are not dried prior to processing with
conventional papermaking fibers.

[0034] In particularly preferred embodiments macroalgae fibers are
provided as dry lap pulps, a fibrous web having a basis weight of at
least about 150 grams per square meter (gsm) and a moisture content of
less than about 30 percent and more preferably less than about 20
percent, such as from about 1 to about 10 percent moisture. The
macroalgae pulps are preferably provided as a blend of macroalgae pulp
fiber and conventional papermaking fibers, such that the pulp comprises
less than about 30 percent macroalgae fibers by weight. The dry lap pulps
may be manufactured by blending never-dried macroalgae fibers with
conventional papermaking fibers, forming a wet fiber web from the blended
fibers and then drying the fiber web to form dry pulp sheets. The
resulting pulp sheets surprisingly have improved strength and durability
compared to both pulp sheets formed from dried macroalgae fibers and pulp
sheets formed from conventional papermaking fibers alone. Further, pulps
prepared as described herein are readily dispersible using traditional
processing equipment, such as hydropulpers.

[0035] Regardless of the species or particular average fiber length,
tissue webs of the present disclosure comprise at least about 0.5 percent
macroalgae by total weight of the web and more preferably at least about
1 percent and still more preferably from about 2 to about 5 percent. The
tissue webs comprising macroalgae may be either blended or layered webs.
Where the webs are multi-layered, they may be layered such that one layer
is substantially free from macroalgae fibers, while another layer
comprises conventional papermaking and macroalgae fibers. It should be
understood that, when referring to a layer that is substantially free of
macroalgae fibers, negligible amounts of the fibers may be present
therein, however, such small amounts often arise from the macroalgae
fibers applied to an adjacent layer, and do not typically substantially
affect the softness or other physical characteristics of the web.

[0036] Conventional papermaking fibers may comprise wood pulp fibers
formed by a variety of pulping processes, such as kraft pulp, sulfite
pulp, thermomechanical pulp, and the like. Further, the wood fibers may
be any high-average fiber length wood pulp, low-average fiber length wood
pulp, or mixtures of the same. One example of suitable high-average
length wood pulp fibers include softwood fibers such as, but not limited
to, northern softwood, southern softwood, redwood, red cedar, hemlock,
pine (e.g., southern pines), spruce (e.g., black spruce), combinations
thereof, and the like. One example of suitable low-average length wood
pulp fibers include hardwood fibers, such as, but not limited to,
eucalyptus, maple, birch, aspen, and the like. In certain instances,
eucalyptus fibers may be particularly desired to increase the softness of
the web. Eucalyptus fibers can also enhance the brightness, increase the
opacity, and change the pore structure of the web to increase its wicking
ability. Moreover, if desired, secondary fibers obtained from recycled
materials may be used, such as fiber pulp from sources such as, for
example, newsprint, reclaimed paperboard, and office waste.

[0037] In a particularly preferred embodiment macroalgae fibers are
utilized in the tissue web as a replacement for low average fiber length
wood fibers such as hardwood fibers and more specifically Eucalyptus
kraft fibers. In one particular embodiment, macroalgae fibers are
incorporated into a multi-layered web having a middle layer disposed
between an air contacting layer (non-fabric contacting layer) and a
fabric contacting layer where the air contacting layer comprises a blend
of hardwood fibers and macroalgae fibers, the middle layer comprises
softwood fibers and the fabric contacting layer comprises hardwood fibers
and is substantially free from macroalgae fibers. In such embodiments the
macroalgae fiber may be added to the air contacting layer such that the
total web comprises about 0.5 percent by total weight of the web
macroalgae fibers, such as from about 1 to about 5 percent and more
preferably from about 2 to about 3 percent.

[0038] In addition to varying the amount of macroalgae within the web, as
well as the amount in any given layer, the physical properties of the web
may be varied by specifically selecting a particular layer or layers for
incorporation of the macroalgae fibers. It has now been discovered that
the greatest increase in tensile is achieved by selectively incorporating
the macroalgae fibers in a multi-layered web such that the layer
comprising macroalgae is not brought into contact with the forming fabric
during formation of the web.

[0039] In a particularly preferred embodiment, the present disclosure
provides a tissue web having enhanced tensile strength without a
corresponding increase in stiffness, where the multi-layered tissue web
comprises fabric and non-fabric contacting layers, wherein the fabric
contacting fibrous layer comprises conventional papermaking fibers and is
substantially free from macroalgae fibers and the non-fabric contacting
fibrous layer comprises conventional papermaking fibers and macroalgae
fibers. Preferably the webs have a tensile strength greater than about
500 g/3'', such as from about 500 to about 1000 g/3'', and more
preferably from about 700 to about 800 g/3'', yet have a Stiffness Index
less than about 10, and more preferably less than about 9, such as from
about 7 to about 9.

[0040] In still other embodiments, the present disclosure provides tissue
webs having enhanced bulk, softness and durability. Improved durability,
such as increased machine and cross-machine direction stretch (MD Stretch
and CD Stretch), and improved softness may be measured as a reduction in
the slope of the tensile-strain curve (measured as GM Slope) or the
Stiffness Index. For example, tissue webs prepared as described herein
generally have a GM Slope less than about 9.0 kgf, such as from about 6.0
to about 9.0 kgf and more preferably from about 6.5 to about 7.5 kgf. The
GM Slopes are achieved at relatively modest tensile strengths, such as a
GMT from about 700 to about 900 g/3'', yielding Stiffness Indexes from
about 7 to about 9.

[0041] Similarly, webs may also have MD Stretch from greater than about 12
percent and more preferably greater than about 15 percent, such as from
about 15 to about 20 percent, yielding webs having Machine Direction
Durability greater than about 10, such as from about 10 to about 12 and
more preferably from about 10.5 to about 11.5.

[0042] Webs prepared as described herein may be converted into either
single or multi-ply rolled tissue products that have improved properties
over the prior art. In one embodiment the present disclosure provides a
rolled tissue product comprising a spirally wound tissue web having at
least two layers wherein the air contacting layer comprising less than
about 5 percent macroalgae by weight of the web and wherein the tissue
web has a bone dry basis weight greater than about 35 gsm, a sheet bulk
greater than about 15 cc/g and a Stiffness Index less than about 9.

[0043] The tissue webs may also be incorporated into tissue products that
may be either single- or multi-ply, where one or more of the plies may be
formed by a multi-layered tissue web having macroalgae fibers selectively
incorporated in one of its layers. In one embodiment the tissue product
is constructed such that the macroalgae fibers are brought into contact
with the user's skin in-use. For example, the tissue product may comprise
two multi-layered through-air dried webs wherein each web comprises a
fabric contacting fibrous layer substantially free from macroalgae and a
non-fabric contacting fibrous layer comprising macroalgae. The webs are
plied together such that the outer surface of the tissue product is
formed from the fabric contacting fibrous layers of each web, such that
the surface brought into contact with the user's skin in-use comprises
macroalgae fibers.

[0044] If desired, various chemical compositions may be applied to one or
more layers of the multi-layered tissue web to further enhance softness
and/or reduce the generation of lint or slough. For example, in some
embodiments, a wet strength agent can be utilized to further increase the
strength of the tissue product when wet. As used herein, a "wet strength
agent" is any material that when added to pulp fibers can provide a
resulting web or sheet with a wet geometric tensile strength to dry
geometric tensile strength ratio in excess of about 0.1. Typically these
materials are termed either "permanent" wet strength agents or
"temporary" wet strength agents. As is well known in the art, temporary
and permanent wet strength agents may also sometimes function as dry
strength agents to enhance the strength of the tissue product when dry.

[0045] Wet strength agents may be applied in various amounts depending on
the desired characteristics of the web. For instance, in some
embodiments, the total amount of wet strength agents added can be between
about 1 to about 60 pounds per ton (lbs/T), in some embodiments between
about 5 to about 30 lbs/T, and in some embodiments between about 7 to
about 13 lbs/T of the dry weight of fibrous material. The wet strength
agents can be incorporated into any layer of the multi-layered tissue
web.

[0046] A chemical debonder can also be applied to soften the web.
Specifically, a chemical debonder can reduce the amount of hydrogen bonds
within one or more layers of the web, which results in a softer product.
Depending on the desired characteristics of the resulting tissue product,
the debonder can be utilized in varying amounts. For example, in some
embodiments, the debonder can be applied in an amount between about 1 to
about 30 lbs/T, in some embodiments between about 3 to about 20 lbs/T,
and in some embodiments, between about 6 to about 15 lbs/T of the dry
weight of fibrous material. The debonder can be incorporated into any
layer of the multi-layered tissue web.

[0047] Any material capable of enhancing the soft feel of a web by
disrupting hydrogen bonding can generally be used as a debonder in the
present invention. In particular, as stated above, it is typically
desired that the debonder possess a cationic charge for forming an
electrostatic bond with anionic groups present on the pulp. Some examples
of suitable cationic debonders can include, but are not limited to,
quaternary ammonium compounds, imidazolinium compounds, bis-imidazolinium
compounds, diquaternary ammonium compounds, polyquaternary ammonium
compounds, ester-functional quaternary ammonium compounds (e.g.,
quaternized fatty acid trialkanolamine ester salts), phospholipid
derivatives, polydimethylsiloxanes and related cationic and non-ionic
silicone compounds, fatty and carboxylic acid derivatives, mono and
polysaccharide derivatives, polyhydroxy hydrocarbons, etc. For instance,
some suitable debonders are described in U.S. Pat. Nos. 5,716,498,
5,730,839, 6,211,139, 5,543,067, and WO/0021918, all of which are
incorporated herein in a manner consistent with the present disclosure.

[0048] Still other suitable debonders are disclosed in U.S. Pat. Nos.
5,529,665 and 5,558,873, both of which are incorporated herein in a
manner consistent with the present disclosure. In particular, U.S. Pat.
No. 5,529,665 discloses the use of various cationic silicone compositions
as softening agents.

[0049] Tissue webs of the present disclosure can generally be formed by
any of a variety of papermaking processes known in the art. Preferably
the tissue web is formed by through-air drying and be either creped or
uncreped. For example, a papermaking process of the present disclosure
can utilize adhesive creping, wet creping, double creping, embossing,
wet-pressing, air pressing, through-air drying, creped through-air
drying, uncreped through-air drying, as well as other steps in forming
the paper web. Some examples of such techniques are disclosed in U.S.
Pat. Nos. 5,048,589, 5,399,412, 5,129,988 and 5,494,554 all of which are
incorporated herein in a manner consistent with the present disclosure.
When forming multi-ply tissue products, the separate plies can be made
from the same process or from different processes as desired.

[0050] For example, in one embodiment, tissue webs may be creped
through-air dried webs formed using processes known in the art. To form
such webs, an endless traveling forming fabric, suitably supported and
driven by rolls, receives the layered papermaking stock issuing from the
headbox. A vacuum box is disposed beneath the forming fabric and is
adapted to remove water from the fiber furnish to assist in forming a
web. From the forming fabric, a formed web is transferred to a second
fabric, which may be either a wire or a felt. The fabric is supported for
movement around a continuous path by a plurality of guide rolls. A pick
up roll designed to facilitate transfer of web from fabric to fabric may
be included to transfer the web.

[0051] Preferably the formed web is dried by transfer to the surface of a
rotatable heated dryer drum, such as a Yankee dryer. The web may be
transferred to the Yankee directly from the throughdrying fabric or,
preferably, transferred to an impression fabric which is then used to
transfer the web to the Yankee dryer. In accordance with the present
disclosure, the creping composition of the present disclosure may be
applied topically to the tissue web while the web is traveling on the
fabric or may be applied to the surface of the dryer drum for transfer
onto one side of the tissue web. In this manner, the creping composition
is used to adhere the tissue web to the dryer drum. In this embodiment,
as the web is carried through a portion of the rotational path of the
dryer surface, heat is imparted to the web causing most of the moisture
contained within the web to be evaporated. The web is then removed from
the dryer drum by a creping blade. The creping web as it is formed
further reduces internal bonding within the web and increases softness.
Applying the creping composition to the web during creping, on the other
hand, may increase the strength of the web.

[0052] In another embodiment the formed web is transferred to the surface
of the rotatable heated dryer drum, which may be a Yankee dryer. The
press roll may, in one embodiment, comprise a suction pressure roll. In
order to adhere the web to the surface of the dryer drum, a creping
adhesive may be applied to the surface of the dryer drum by a spraying
device. The spraying device may emit a creping composition made in
accordance with the present disclosure or may emit a conventional creping
adhesive. The web is adhered to the surface of the dryer drum and then
creped from the drum using the creping blade. If desired, the dryer drum
may be associated with a hood. The hood may be used to force air against
or through the web.

[0053] In other embodiments, once creped from the dryer drum, the web may
be adhered to a second dryer drum. The second dryer drum may comprise,
for instance, a heated drum surrounded by a hood. The drum may be heated
from about 25 to about 200° C., such as from about 100 to about
150° C.

[0054] In order to adhere the web to the second dryer drum, a second spray
device may emit an adhesive onto the surface of the dryer drum. In
accordance with the present disclosure, for instance, the second spray
device may emit a creping composition as described above. The creping
composition not only assists in adhering the tissue web to the dryer
drum, but also is transferred to the surface of the web as the web is
creped from the dryer drum by the creping blade.

[0055] Once creped from the second dryer drum, the web may, optionally, be
fed around a cooling reel drum and cooled prior to being wound on a reel.

[0056] For example, once a fibrous web is formed and dried, in one aspect,
the creping composition may be applied to at least one side of the web
and the at least one side of the web may then be creped. In general, the
creping composition may be applied to only one side of the web and only
one side of the web may be creped, the creping composition may be applied
to both sides of the web and only one side of the web is creped, or the
creping composition may be applied to each side of the web and each side
of the web may be creped.

[0057] Once creped the tissue web may be pulled through a drying station.
The drying station can include any form of a heating unit, such as an
oven energized by infra-red heat, microwave energy, hot air, or the like.
A drying station may be necessary in some applications to dry the web
and/or cure the creping composition. Depending upon the creping
composition selected, however, in other applications a drying station may
not be needed.

[0058] In other embodiments, the base web is formed by an uncreped
through-air drying process such as those described, for example, in U.S.
Pat. Nos. 5,656,132 and 6,017,417, both of which are hereby incorporated
by reference herein in a manner consistent with the present disclosure.
The uncreped through-air drying process may comprise a twin wire former
having a papermaking headbox which injects or deposits a furnish of an
aqueous suspension of wood fibers onto a plurality of forming fabrics,
such as an outer forming fabric and an inner forming fabric, thereby
forming a wet tissue web. The forming process may be any conventional
forming process known in the papermaking industry. Such formation
processes include, but are not limited to, Fourdriniers, roof formers
such as suction breast roll formers, and gap formers such as twin wire
formers and crescent formers.

[0059] The wet tissue web forms on the inner forming fabric as the inner
forming fabric revolves about a forming roll. The inner forming fabric
serves to support and carry the newly-formed wet tissue web downstream in
the process as the wet tissue web is partially dewatered to a consistency
of about 10 percent based on the dry weight of the fibers.

[0060] Additional dewatering of the wet tissue web may be carried out by
known paper making techniques, such as vacuum suction boxes, while the
inner forming fabric supports the wet tissue web. The wet tissue web may
be additionally dewatered to a consistency of at least about 20 percent,
more specifically between about 20 to about 40 percent, and more
specifically about 20 to about 30 percent.

[0061] The forming fabric can generally be made from any suitable porous
material, such as metal wires or polymeric filaments. For instance, some
suitable fabrics can include, but are not limited to, Albany 84M and 94M
available from Albany International (Albany, N.Y.) Asten 856, 866, 867,
892, 934, 939, 959, or 937; Asten Synweve Design 274, all of which are
available from Asten Forming Fabrics, Inc. (Appleton, Wis.); and Voith
2164 available from Voith Fabrics (Appleton, Wis.). The wet web is then
transferred from the forming fabric to a transfer fabric while at a
solids consistency of between about 10 to about 35 percent and,
particularly, between about 20 to about 30 percent. As used herein, a
"transfer fabric" is a fabric that is positioned between the forming
section and the drying section of the web manufacturing process.

[0062] Transfer to the transfer fabric may be carried out with the
assistance of positive and/or negative pressure. For example, in one
embodiment, a vacuum shoe can apply negative pressure such that the
forming fabric and the transfer fabric simultaneously converge and
diverge at the leading edge of the vacuum slot. Typically, the vacuum
shoe supplies pressure at levels between about 10 to about 25 inches of
mercury. As stated above, the vacuum transfer shoe (negative pressure)
can be supplemented or replaced by the use of positive pressure from the
opposite side of the web to blow the web onto the next fabric. In some
embodiments, other vacuum shoes can also be used to assist in drawing the
fibrous web onto the surface of the transfer fabric.

[0063] Typically, the transfer fabric travels at a slower speed than the
forming fabric to enhance the MD and CD stretch of the web, which
generally refers to the stretch of a web in its cross (CD) or machine
direction (MD) (expressed as percent elongation at sample failure). For
example, the relative speed difference between the two fabrics can be
from about 1 to about 30 percent, in some embodiments from about 5 to
about 20 percent, and in some embodiments, from about 10 to about 15
percent. This is commonly referred to as "rush transfer." During "rush
transfer," many of the bonds of the web are believed to be broken,
thereby forcing the sheet to bend and fold into the depressions on the
surface of the transfer fabric 8. Such molding to the contours of the
surface of the transfer fabric 8 may increase the MD and CD stretch of
the web. Rush transfer from one fabric to another can follow the
principles taught in any one of the following patents, U.S. Pat. Nos.
5,667,636, 5,830,321, 4,440,597, 4,551,199, 4,849,054, all of which are
hereby incorporated by reference herein in a manner consistent with the
present disclosure. The wet tissue web is then transferred from the
transfer fabric to a throughdrying fabric.

[0064] While supported by the throughdrying fabric, the wet tissue web is
dried to a final consistency of about 94 percent or greater by a
throughdryer. The drying process can be any noncompressive drying method
which tends to preserve the bulk or thickness of the wet web including,
without limitation, throughdrying, infra-red radiation, microwave drying,
etc. Because of its commercial availability and practicality,
throughdrying is well known and is one commonly used means for
noncompressively drying the web for purposes of this invention. Suitable
throughdrying fabrics include, without limitation, fabrics with
substantially continuous machine direction ridges whereby the ridges are
made up of multiple warp strands grouped together, such as those
disclosed in U.S. Pat. No. 6,998,024. Other suitable throughdrying
fabrics include those disclosed in U.S. Pat. No. 7,611,607, which is
incorporated herein in a manner consistent with the present disclosure,
particularly the fabrics denoted as Fred (t1207-77), Jetson (t1207-6) and
Jack (t1207-12). The web is preferably dried to final dryness on the
throughdrying fabric, without being pressed against the surface of a
Yankee dryer, and without subsequent creping.

[0065] Additionally, webs prepared according to the present disclosure may
be subjected to any suitable post processing including, but not limited
to, printing, embossing, calendering, slitting, folding, combining with
other fibrous structures, and the like.

Test Methods

Tensile

[0066] Samples for tensile strength testing are prepared by cutting a 3''
(76.2 mm)×5'' (127 mm) long strip in either the machine direction
(MD) or cross-machine direction (CD) orientation using a JDC Precision
Sample Cutter (Thwing-Albert Instrument Company, Philadelphia, Pa., Model
No. JDC 3-10, Ser. No. 37333). The instrument used for measuring tensile
strengths is an MTS Systems Sintech 11S, Serial No. 6233. The data
acquisition software is MTS TestWorks® for Windows Ver. 4 (MTS Systems
Corp., Research Triangle Park, N.C.). The load cell is selected from
either a 50 Newton or 100 Newton maximum, depending on the strength of
the sample being tested, such that the majority of peak load values fall
between 10 and 90 percent of the load cell's full scale value. The gauge
length between jaws is 2±0.04 inches (50.8±1 mm). The jaws are
operated using pneumatic-action and are rubber coated. The minimum grip
face width is 3'' (76.2 mm), and the approximate height of a jaw is 0.5
inches (12.7 mm). The crosshead speed is 10±0.4 inches/min (254±1
mm/min), and the break sensitivity is set at 65 percent. The sample is
placed in the jaws of the instrument, centered both vertically and
horizontally. The test is then started and ends when the specimen breaks.
The peak load is recorded as either the "MD tensile strength" or the "CD
tensile strength" of the specimen depending on the sample being tested.
At least six (6) representative specimens are tested for each product,
taken "as is," and the arithmetic average of all individual specimen
tests is either the MD or CD tensile strength for the product.

[0068] Dry lap red algae pulp ("RA") was prepared by blending EHWK with
wet red algae pulp and forming a dry lap pulp sheet using a Fourdrinier
machine comprising a wire forming section, a suction box, a pair of
registered wet press rolls, and three cylindrical air dryers. Each fiber
type was weighed individually and dispersed in a pulper for 25 to 30
minutes, yielding a fiber slurry with a consistency of 3 percent, and
then returned to a stock tank for use in the formation of the pulp sheet.
The entire stock preparation system was heated to 50° C.

[0069] The fiber slurries were mixed depending on the desired blend of the
dry lap pulp and then pumped to the headbox and deposited onto the
forming section of the paper machine under pressure to increase drainage.
The resulting fibrous web was pressed to further remove water using
weight of the first press roll, which was adjusted to maximize caliper.
The dewatered fibrous web was subjected to drying using a series of dryer
cans, the initial dryer can pressure was 100 pounds per square inch
(psig) in the first, second, and third section, corresponding to about
177° C. The resulting dry lap pulp sheet had a moisture content of
less than about 10 percent and a basis weight of about 230 gsm.

[0070] A single ply through-air dried tissue web was made generally in
accordance with U.S. Pat. No. 5,607,551, which is herein incorporated by
reference in a manner consistent with the present disclosure. Initially
NSWK was dispersed in a pulper for 30 minutes at 3 percent consistency at
about 100° F. The NSWK was then transferred to a dump chest and
subsequently diluted to approximately 0.75 percent consistency. EHWK was
dispersed in a pulper for 30 minutes at about 3 percent consistency at
about 100° F. The EHWK was then transferred to a dump chest and
subsequently diluted to about 0.75 percent consistency. Two separate
dispersions of red algae (RA) dry lap pulp were prepared depending upon
which layer of the tissue web the red algae was to be added to. Dry lap
red algae pulps (80 wt % EHWK and 20 wt % red algae) prepared as
described above were dispersed in a pulper for 30 minutes at about 3
percent consistency at about 100° F. and then transferred to a
dump chest and subsequently diluted to about 0.75 percent consistency.

[0071] The pulp slurries were subsequently pumped to separate machine
chests and further diluted to a consistency of about 0.1 percent. Pulp
fibers from each machine chest were sent through separate manifolds in
the headbox to create a 3-layered tissue structure. The flow rates of the
stock pulp fiber slurries into the flow spreader were adjusted to give a
target web basis. The fiber compositions of the layered sheets are
described in Table 4 below. The formed web was non-compressively
dewatered and rush transferred to a transfer fabric traveling at a speed
about 28 percent slower than the forming fabric. The web was then
transferred to a throughdrying fabric and dried.

[0072] The base sheet webs were converted into various bath tissue rolls.
Specifically, base sheet was calendered using one or two conventional
polyurethane/steel calenders comprising either a 4 or a 40 P&J
polyurethane roll on the air contacting side of the sheet and a standard
steel roll on the fabric contacting side. Table 4 shows the process
conditions for each of the samples prepared in accordance with the
present example. Tables 5 and 6 summarize the physical properties of the
finished product.

[0074] While tissue webs and products comprising the same have been
described in detail with respect to the specific embodiments thereof, it
will be appreciated that those skilled in the art, upon attaining an
understanding of the foregoing, may readily conceive of alterations to,
variations of, and equivalents to these embodiments. Accordingly, the
scope of the present invention should be assessed as that of the appended
claims and any equivalents thereto.